setstate prevstate code example

Example 1: react prevstate

handleClick() {
  this.setState(prevState => ({
    isToggleOn: !prevState.isToggleOn
  }));
}

Example 2: prevstate in usestate

const [prevState, setState] = React.useState([]);

setState(prevState => [...prevState, 'somedata'] );

Example 3: setstate react js

constructor(props) {
        super(props);
        this.state = {
            isActive: true,
        };
    }

    checkStatus = () => {
        this.setState({		// use this function
            'isActive' : !this.state.isActive,
        });
    }

Example 4: this.setstate prevstate

this.setState(prevState => ({ n: !prevState.n }))

Example 5: how to use setstate

class App extends React.Component {

state = { count: 0 }

handleIncrement = () => {
  this.setState({ count: this.state.count + 1 })
}

handleDecrement = () => {
  this.setState({ count: this.state.count - 1 })
}
  render() {
    return (
      

        

          {this.state.count}
        
        Increment by 1
        Decrement by 1
      
    )
  }
}

Example 6: prevstate in react

handleClick() {
        this.setState(prevState => {
            return {
                count: prevState.count + 1
            }
        })
    }